# Draft California 2012 Integrated Report( 303(d) List/305(b) Report)

# Supporting Information

## Regional Board 6 - Lahontan Region

Water Body Name: | Susan River (Headwaters to Susanville)
Water Body ID: | CAR6372001020080815005311
Water Body Type: | River & Stream

DECISION ID | 28278 | Region 6
Susan River (Headwaters to Susanville)

Pollutant: | Mercury
Final Listing Decision: | Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | Do Not Delist from 303(d) list (TMDL required list)(2010)
Revision Status | Original
Sources: | Source Unknown
Expected TMDL Completion Date: | 2019
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | Regional Board Conclusion: This pollutant was considered for removal on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: The State Water Board listed the Susan River as a whole for mercury during the 2006 assessment cycle on the basis of trout tissue samples that exceeded OEHHA fish consumption criteria. The trout were collected at stations above and below Susanville. The river was divided into three segments for the 2008 assessment cycle, and this decision documents continued listing for the upstream segment. There is no known fish passage barrier between this and the next downstream segment. No new data were reviewed for 2008. This pollutant is being considered for removal from the section 303(d) list under section 4.5 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess pollutant. Two samples exceed the OEHHA tissue criterion. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. Two of 4 samples exceeded the tissue criterion however this sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are being met. 4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.
Regional Board Staff Decision Recommendation: | No new data were assessed for this assessment cycle. The conclusion reached in the previous cycle remains the same. The Regional Board will update this decision when new data and information become available in a future assessment cycle.

Line of Evidence (LOE) for Decision ID 28278, Mercury | Region 6
Susan River (Headwaters to Susanville)
LOE ID: | 6686
Pollutant: | Mercury
LOE Subgroup: | Pollutant-Tissue
Matrix: | Tissue
Fraction: | Total
Beneficial Use: | Commercial or recreational collection of fish, shellfish, or organisms
Number of Samples: | 4
Number of Exceedances: | 2
Data and Information Type: | Fish tissue analysis
Data Used to Assess Water Quality: | Two out of 4 samples exceeded. Four filet composite samples, two each, of rainbow trout and brook trout were collected. Rainbow trout were collected in 1998-99. Brook trout were collected in 1999 and 2001. The 1999 rainbow and brook trout samples exceeded the guideline. Both sampled stations exceeded the guideline in 1999 (TSMP, 2002).
Data Reference: | Placeholder reference 2006 303(d)
SWAMP Data: | Non-SWAMP
Water Quality Objective/Criterion: | Lahontan RWQCB Basin Plan: All waters shall be maintained free of toxic substances in concentrations that are toxic to, or produce detrimental physiological responses in human, plant, animal, or aquatic life.
Objective/Criterion Reference: | Placeholder reference 2006 303(d)
Evaluation Guideline: | OEHHA Screening Value 0.3 μg/g (Brodberg & Pollock, 1999).
Guideline Reference: | Placeholder reference 2006 303(d)
Spatial Representation: | Two stations were sampled: just upstream of HWY 36 bridge on the Susan River (Susanville) and downstream of Piute Creek mouth at Alexander Street bridge (Piute Creek).
Temporal Representation: | Samples were collected annually in 1998-99 and 2001.
Environmental Conditions: |
QAPP Information: | Environmental Chemistry Quality Assurance and Data Report for the Toxic Substances Monitoring Program, 1996-2000. Department of Fish and Game. Environmental Chemistry Quality Assurance and Data Report for the Toxic Substances Monitoring Program, 2001-2002. Department of Fish and Game.
QAPP Information Reference(s):

DECISION ID | 30276 | Region 6
Susan River (Headwaters to Susanville)

Pollutant: | Unknown Toxicity
Final Listing Decision: | Do Not Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | Do Not Delist from 303(d) list (TMDL required list)(2010)
Revision Status | Original
Sources: | Source Unknown
Expected TMDL Completion Date: | 2019
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | Regional Board Conclusion: This pollutant was removal for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: The Susan River as a whole was listed for "Unknown Toxicity" in the 1990s. The river was divided into segments for the 2008 cycle. This decision carries the 2006 listing over to one of the new segments. A new University of California Davis study confirmed that toxicity is still present but did not determine the cause. This pollutant is being considered for removal from the section 303(d) list under section 4.6 of the Listing Policy. Under this section a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess pollutant. Four of 12 samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against removing this water segment-pollutant combination from the section 303(d) list. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. Four of 12 samples exceeded the water quality objective and this exceeds the allowable frequency listed in Table 4.1 of the Listing Policy. 4. Pursuant to section 4.11 of the Listing Policy, no additional data and information are available indicating that standards are met.
Regional Board Staff Decision Recommendation: | No new data were assessed for this assessment cycle. The conclusion reached in the previous cycle remains the same. The Regional Board will update this decision when new data and information become available in a future assessment cycle.

Line of Evidence (LOE) for Decision ID 30276, Unknown Toxicity | Region 6
Susan River (Headwaters to Susanville)
LOE ID: | 6683
Pollutant: | Unknown Toxicity
LOE Subgroup: | Toxicity
Matrix: | Water
Fraction: | Not Recorded
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 0
Number of Exceedances: | 0
Data and Information Type: | Not Specified
Data Used to Assess Water Quality: | Unspecified--This LOE is a placeholder to support a 303(d) listing decision made prior to 2006. For 2008 assessment purposes, the Susan River has been split into segments. The 2006 303d placeholder LOEs apply to all new segments.
Data Reference: | Placeholder reference pre-2006 303(d)
SWAMP Data: | Non-SWAMP
Water Quality Objective/Criterion: |
Objective/Criterion Reference:
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: |
Temporal Representation: |
Environmental Conditions: |
QAPP Information: | Unspecified
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30276, Unknown Toxicity | Region 6
Susan River (Headwaters to Susanville)
LOE ID: | 27168
Pollutant: | Unknown Toxicity
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 12
Number of Exceedances: | 4
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.C. Davis Aquatic Toxicology Laboratory sampled the Susan River monthly between May 2003 and August 2004 and tested each sample with three different organisms. Four of 12 samples for Station SR1 showed at least one toxic response.
Data Reference: | 2005. Susan River Toxicity Testing Project, Final Report May 2003-August 2004. University of California Davis Aquatic Toxicity Laboratory. Contract # 02-107-250-0 with Lahontan RWQCB and SWRCB
SWAMP Data: | Non-SWAMP
Water Quality Objective/Criterion: | The Lahontan Basin Plan's narrative water quality objective for Toxicty provides that: "All waters shall be maintained free of toxic substances in concentrations that are toxic to, or that produce detrmental physiological responses in human, plant, animal or aquatic life."
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station in this segment (SR1, Susan River at Hobo Camp trailhead) was sampled.
Temporal Representation: | Twelve monthly samples were collected between May 2003 and August 2004.
Environmental Conditions: | The Susan River is an internally drained river in eastern Lassen County with its headwaters near Lassen Volcanic National Park and its terminus in Honey Lake in the Great Basin. The Susan River is designated for both the Warm Freshwater Habitat and Cold Freshwater Habitat beneficial uses, and for the Spawning, Reproduction and Development and Migration of Aquatic Organisms uses.
QAPP Information: | The UC Davis Aquatic Toxicology Laboratory prepared a QAPP for the study that was acceptable to RWQCB staff. Quality Assurance procedures are summarized in the contract report.
QAPP Information Reference(s):

DECISION ID | 21342 | Region 6
Susan River (Headwaters to Susanville)

Pollutant: | Chloride
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)(2010)
Revision Status | Original
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. None of 16 samples exceeded the Maximum Contaminant Level. Four of five annual average datapoints exceeded the site-specific water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. Quarterly samples do not capture the seasonal and annual variability expected in streamflows and constituent concentrations in streams of the Lahontan Region. 3. None of 16 samples exceeded the Maximum Contaminant Level. Four out of five annual average datapoints exceeded the site-specific objective and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | No new data were assessed for this assessment cycle. The conclusion reached in the previous cycle remains in same. The Regional Board will update this decision when new data and information become available in a future assessment cycle.

Line of Evidence (LOE) for Decision ID 21342, Chloride | Region 6
Susan River (Headwaters to Susanville)
LOE ID: | 6914
Pollutant: | Chloride
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 5
Number of Exceedances: | 4
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled the Susan River under the Region 6 SWAMP program between 2001 and 2005. Chloride concentrations in 16 quarterly samples (3-4 per year) ranged from below the detection level to 2.08 mg/L. One of the annual averages was an estimate; the other average values ranged from 0.71 to 1.19 mg/L. The annual average objective was exceeded in four of 5 years.
Data Reference: | 2007. SWAMP Data for the Susan River
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | The site-specific objective from Lahontan Basin Plan Table 3-9 includes an annual average chloride concentration of 0.7 mg/L and a 90th percentile value of 1.0 mg/L.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station (Susan River above confluence with Willard Creek) was sampled.
Temporal Representation: | Sixteen quarterly samples (3 to 4 per year) were collected between 2001 and 2005.
Environmental Conditions: | The Susan River is an internally drained river in eastern Lassen County with its headwaters near Lassen Volcanic National Park and its terminus in Honey Lake in the Great Basin. The Susan River is designated for both the Warm Freshwater Habitat and Cold Freshwater Habitat beneficial uses, and for the Spawning, Reproduction and Development and Migration of Aquatic Organisms uses.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 21342, Chloride | Region 6
Susan River (Headwaters to Susanville)
LOE ID: | 6915
Pollutant: | Chloride
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Municipal & Domestic Supply
Number of Samples: | 16
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled the Susan River under the Region 6 SWAMP program between 2001 and 2005. Chloride concentrations in 16 quarterly samples ranged from below the detection level to 2.08 mg/L. The MCL was not exceeded.
Data Reference: | 2007. SWAMP Data for the Susan River
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | California Maximum Contaminant Levels (MCLs) apply to ambient waters under the Lahontan Basin Plan's "Chemical Constituents" objective. The MCL for chloride is 250 mg/L.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station (Susan River above confluence with Willard Creek) was sampled.
Temporal Representation: | Sixteen quarterly samples (3 to 4 per year) were collected between 2001 and 2005.
Environmental Conditions: | The Susan River is an internally drained river in eastern Lassen County with its headwaters near Lassen Volcanic National Park and its terminus in Honey Lake in the Great Basin. The Susan River is designated for both the Warm Freshwater Habitat and Cold Freshwater Habitat beneficial uses, and for the Spawning, Reproduction and Development and Migration of Aquatic Organisms uses.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30092 | Region 6
Susan River (Headwaters to Susanville)

Pollutant: | Dissolved oxygen saturation
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)(2010)
Revision Status | Original
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceeds the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. One of the datasets used satisfies the data quality requirements of section 6.1.4 of the Policy. The other does not. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy.The limited sample numbers do not capture the seasonal and annual variability expected in streamflows and dissolved oxygen concentrations in streams of the Lahontan Region. 3. None of three SWAMP samples and none of two USBLM samples exceeded the water quality objective and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | No new data were assessed for this assessment cycle. The conclusion reached in the previous cycle remains in same. The Regional Board will update this decision when new data and information become available in a future assessment cycle.

Line of Evidence (LOE) for Decision ID 30092, Dissolved oxygen saturation | Region 6
Susan River (Headwaters to Susanville)
LOE ID: | 6918
Pollutant: | Dissolved oxygen saturation
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 3
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled the Susan River under the Region 6 SWAMP program. Percent saturation of dissolved oxygen was measured on 10/20/2004, 1/25/ 2005 and 7/20/2005. Percent saturation ranged from 104 to 105 percent. The objective was not violated.
Data Reference: | 2007. SWAMP Data for the Susan River
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | The narrative objective in the Lahontan Basin Plan states that percent saturation shall not be depressed by more than 10 percent and minimum dissolved oxygen concentration shall not be less than 80 percent saturation.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station (Susan River above confluence with Willard Creek) was sampled.
Temporal Representation: | Three measurements of percent saturation of dissolved oxygen were taken between October 2004 and July 2005.
Environmental Conditions: | The Susan River is an internally drained river in eastern Lassen County with its headwaters near Lassen Volcanic National Park and its terminus in Honey Lake in the Great Basin. The Susan River is designated for both the Warm Freshwater Habitat and Cold Freshwater Habitat beneficial uses, and for the Spawning, Reproduction and Development and Migration of Aquatic Organisms uses.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30092, Dissolved oxygen saturation | Region 6
Susan River (Headwaters to Susanville)
LOE ID: | 26011
Pollutant: | Dissolved oxygen saturation
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Bureau of Land Management sampled the Susan River in July and August 2002. Dissolved oxygen saturation levels in two samples were 104.8 and 96.3 percent.
Data Reference: | Water quality data for surface waters on U.S Bureau of Land Management lands in Lassen and Modoc Counties
SWAMP Data: | Non-SWAMP
Water Quality Objective/Criterion: | The narrative objective in the Lahontan Basin Plan states that percent saturation shall not be depressed by more than 10 percent and minimum dissolved oxygen concentration shall not be less than 80 percent saturation.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | The USBLM sampled three stations, Susan River at Hobo Camp, Susan River at Devils Corral, and Susan River above Cheney Creek.
Temporal Representation: | Samples were collected on June 5, July 16 and August 19, 2002.
Environmental Conditions: | The Susan River is an internally drained river in eastern Lassen County with its headwaters near Lassen Volcanic National Park and its terminus in Honey Lake in the Great Basin. The Susan River is designated for both the Warm Freshwater Habitat and Cold Freshwater Habitat beneficial uses, and for the Spawning, Reproduction and Development and Migration of Aquatic Organisms uses.
QAPP Information: | No quality assurance information was submitted with the USBLM data.
QAPP Information Reference(s):

DECISION ID | 21369 | Region 6
Susan River (Headwaters to Susanville)

Pollutant: | Fecal Coliform
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)(2010)
Revision Status | Original
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutant is being considered for placement on the section 303(d) list under section 3.3 of the Listing Policy. Under section 3.3 a single line of evidence is necessary to assess listing status. Four lines of evidence are available in the administrative record to assess this pollutant. None of the samples from the SWAMP dataset exceed the water quality objective. Two out of 5 samples from the USBLM dataset exceed the objective; however this dataset was submitted without quality assurance information. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The SWAMP data used satisfy the data quality requirements of section 6.1.4 of the Policy. No quality assurance information was submitted with the USBLM data. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. The quarterly SWAMP samples do not capture the seasonal and annual variability expected in streamflows and constituent concentrations in streams of the Lahontan Region. The water quality objective calls for five samples to be collected within a 30-day period. 3. None of eight SWAMP samples exceeded the water quality objective. Two of the 5 USBLM samples exceeded the objective and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: |

Line of Evidence (LOE) for Decision ID 21369, Fecal Coliform | Region 6
Susan River (Headwaters to Susanville)
LOE ID: | 26259
Pollutant: | Fecal Coliform
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Water Contact Recreation
Number of Samples: | 5
Number of Exceedances: | 2
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Bureau of Land Management sampled the Susan River in June, July and August 2002. Five samples had fecal coliform counts ranging from 3 to 59 colonies per 100 mL. Two samples exceeded the limit in the water quality objective.
Data Reference: | Water quality data for surface waters on U.S Bureau of Land Management lands in Lassen and Modoc Counties
SWAMP Data: | Non-SWAMP
Water Quality Objective/Criterion: | The Lahontan Basin Plan's objective for coliform bacteria states: "Waters shall not contain concentrations of coliform organisms attributable to anthropogenic sources, including human and livestock waste. The fecal coliform concentration during any 30-day period shall not exceed a log mean of 20/100 ml, nor shall more than 10 percent of all samples collected during any 30-day period exceed 40/100 ml. The log mean shall ideally be based on a minimum of not less than five samples collected a evenly spaced as practicable during any 30-day period. However, a log mean concentration exceeding 20/100 ml for any 30-day period shall indicate violation of this objective even if fewer than five samples were collected."
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
| Water quality data for surface waters on U.S Bureau of Land Management lands in Lassen and Modoc Counties
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | The USBLM sampled three stations, Susan River at Hobo Camp, Susan River at Devils Corral, and susan River above Cheney Creek.
Temporal Representation: | Samples were collected on June 5, July 16, and August 19, 2002.
Environmental Conditions: | The Susan River is an internally drained river in eastern Lassen County with its headwaters near Lassen Volcanic National Park and its terminus in Honey Lake in the Great Basin. The Susan River is designated for both the Warm Freshwater Habitat and Cold Freshwater Habitat beneficial uses, and for the Spawning, Reproduction and Development and Migration of Aquatic Organisms uses.
QAPP Information: | No quality assurance information was submitted with the USBLM data.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 21369, Fecal Coliform | Region 6
Susan River (Headwaters to Susanville)
LOE ID: | 6921
Pollutant: | Fecal Coliform
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Municipal & Domestic Supply
Number of Samples: | 8
Number of Exceedances: | 0
Data and Information Type: | Water column surveys (e.g. fecal coliform)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled the Susan River under the Region 6 SWAMP program between. Eight quarterly samples for fecal coliform bacteria were collected between September 2003 and July 2005. Seven samples were estimated values and the eighth was below the detection level. The objective was not violated.
Data Reference: | 2007. SWAMP Data for the Susan River
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | The Lahontan Basin Plan's objective for coliform bacteria states: "Waters shall not contain concentrations of coliform organisms attributable to anthropogenic sources, including human and livestock waste. The fecal coliform concentration during any 30-day period shall not exceed a log mean of 20/100 ml, nor shall more than 10 percent of all samples collected during any 30-day period exceed 40/100 ml. The log mean shall ideally be based on a minimum of not less than five samples collected a evenly spaced as practicable during any 30-day period. However, a log mean concentration exceeding 20/100 ml for any 30-day period shall indicate violation of this objective even if fewer than five samples were collected."
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station (Susan River above confluence with Willard Creek) was sampled.
Temporal Representation: | Eight quarterly samples were collected between September 2003 and July 2005.
Environmental Conditions: | The Susan River is an internally drained river in eastern Lassen County with its headwaters near Lassen Volcanic National Park and its terminus in Honey Lake in the Great Basin. The Susan River is designated for both the Warm Freshwater Habitat and Cold Freshwater Habitat beneficial uses, and for the Spawning, Reproduction and Development and Migration of Aquatic Organisms uses.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 21369, Fecal Coliform | Region 6
Susan River (Headwaters to Susanville)
LOE ID: | 26258
Pollutant: | Fecal Coliform
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Municipal & Domestic Supply
Number of Samples: | 5
Number of Exceedances: | 2
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Bureau of Land Management sampled the Susan River in June, July and August 2002. Five samples had fecal coliform counts ranging from 3 to 59 colonies per 100 mL. Two samples exceeded the limit in the water quality objective.
Data Reference: | Water quality data for surface waters on U.S Bureau of Land Management lands in Lassen and Modoc Counties
SWAMP Data: | Non-SWAMP
Water Quality Objective/Criterion: | The Lahontan Basin Plan's objective for coliform bacteria states: "Waters shall not contain concentrations of coliform organisms attributable to anthropogenic sources, including human and livestock waste. The fecal coliform concentration during any 30-day period shall not exceed a log mean of 20/100 ml, nor shall more than 10 percent of all samples collected during any 30-day period exceed 40/100 ml. The log mean shall ideally be based on a minimum of not less than five samples collected a evenly spaced as practicable during any 30-day period. However, a log mean concentration exceeding 20/100 ml for any 30-day period shall indicate violation of this objective even if fewer than five samples were collected."
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
| Water quality data for surface waters on U.S Bureau of Land Management lands in Lassen and Modoc Counties
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | The USBLM sampled three stations, Susan River at Hobo Camp, Susan River at Devils Corral, and susan River above Cheney Creek.
Temporal Representation: | Samples were collected on June 5, July 16, and August 19, 2002.
Environmental Conditions: | The Susan River is an internally drained river in eastern Lassen County with its headwaters near Lassen Volcanic National Park and its terminus in Honey Lake in the Great Basin. The Susan River is designated for both the Warm Freshwater Habitat and Cold Freshwater Habitat beneficial uses, and for the Spawning, Reproduction and Development and Migration of Aquatic Organisms uses.
QAPP Information: | No quality assurance information was submitted with the USBLM data.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 21369, Fecal Coliform | Region 6
Susan River (Headwaters to Susanville)
LOE ID: | 6922
Pollutant: | Fecal Coliform
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Water Contact Recreation
Number of Samples: | 8
Number of Exceedances: | 0
Data and Information Type: | Water column surveys (e.g. fecal coliform)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled the Susan River under the Region 6 SWAMP program between. Eight quarterly samples for fecal coliform bacteria were collected between September 2003 and July 2005. Seven samples were estimated values and the eighth was below the detection level. The objective was not violated.
Data Reference: | 2007. SWAMP Data for the Susan River
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | The Lahontan Basin Plan's objective for coliform bacteria states: "Waters shall not contain concentrations of coliform organisms attributable to anthropogenic sources, including human and livestock waste. The fecal coliform concentration during any 30-day period shall not exceed a log mean of 20/100 ml, nor shall more than 10 percent of all samples collected during any 30-day period exceed 40/100 ml. The log mean shall ideally be based on a minimum of not less than five samples collected a evenly spaced as practicable during any 30-day period. However, a log mean concentration exceeding 20/100 ml for any 30-day period shall indicate violation of this objective even if fewer than five samples were collected."
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station (Susan River above confluence with Willard Creek) was sampled.
Temporal Representation: | Eight quarterly samples were collected between September 2003 and July 2005.
Environmental Conditions: | The Susan River is an internally drained river in eastern Lassen County with its headwaters near Lassen Volcanic National Park and its terminus in Honey Lake in the Great Basin. The Susan River is designated for both the Warm Freshwater Habitat and Cold Freshwater Habitat beneficial uses, and for the Spawning, Reproduction and Development and Migration of Aquatic Organisms uses.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 28355 | Region 6
Susan River (Headwaters to Susanville)

Pollutant: | Nitrate
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)(2010)
Revision Status | Original
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. None of the samples exceeds the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used do not satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. None of five samples exceeded the water quality objective and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | No new data were assessed for this assessment cycle. The conclusion reached in the previous cycle remains in same. The Regional Board will update this decision when new data and information become available in a future assessment cycle.

Line of Evidence (LOE) for Decision ID 28355, Nitrate | Region 6
Susan River (Headwaters to Susanville)
LOE ID: | 26252
Pollutant: | Nitrate
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Municipal & Domestic Supply
Number of Samples: | 5
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Bureau of Land Management sampled the Susan River in June, July and August 2002. Concentrations of NO3-N in 5 samples ranged from 0.15 to 1.32 mg/L. The MCL was not exceeded.
Data Reference: | 2007. SWAMP Data for the Susan River
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | California Maximum Contaminant Levels (MCLs) apply to ambient waters under the Lahontan Basin Plan's "Chemical Constituents" objective. The MCL for nitrate is 45 mg/L expressed "as nitrate," equivalent to 10 mg/L expressed "as N."
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
| Water quality data for surface waters on U.S Bureau of Land Management lands in Lassen and Modoc Counties
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | The USBLM sampled three stations, Susan River at Hobo Camp, Susan River at Devils Corral, and Susan River above Cheney Creek.
Temporal Representation: | Samples were collected on June 5, July 16, and August 19, 2002.
Environmental Conditions: | The Susan River is an internally drained river in eastern Lassen County with its headwaters near Lassen Volcanic National Park and its terminus in Honey Lake in the Great Basin. The Susan River is designated for both the Warm Freshwater Habitat and Cold Freshwater Habitat beneficial uses, and for the Spawning, Reproduction and Development and Migration of Aquatic Organisms uses.
QAPP Information: | No quality assurance information was submitted with the USBLM data.
QAPP Information Reference(s):

DECISION ID | 27349 | Region 6
Susan River (Headwaters to Susanville)

Pollutant: | Nitrate/Nitrite (Nitrite + Nitrate as N)
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)(2010)
Revision Status | Original
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. None of the samples exceeds the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. Quarterly samples do not capture the seasonal and annual variability expected in streamflows and constituent concentrations in streams of the Lahontan Region. 3. None of 16 samples exceeded the California Maximum Contaminant Level and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | No new data were assessed for this assessment cycle. The conclusion reached in the previous cycle remains in same. The Regional Board will update this decision when new data and information become available in a future assessment cycle.

Line of Evidence (LOE) for Decision ID 27349, Nitrate/Nitrite (Nitrite + Nitrate as N) | Region 6
Susan River (Headwaters to Susanville)
LOE ID: | 23453
Pollutant: | Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Municipal & Domestic Supply
Number of Samples: | 16
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled the Susan River under the Region 6 SWAMP program between 2001 and 2005. Sixteen quarterly samples for nitrite plus nitrate included two estimated values and one sample below the detection level. Concentrations in the remainder of the samples ranged from 0.009 to 0.23 mg/L. The MCL was not exceeded.
Data Reference: | 2007. SWAMP Data for the Susan River
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | California Maximum Contaminant Levels (MCLs) apply to ambient waters under the Lahontan Basin Plan's "Chemical Constituents" objective. The MCL for nitrite plus nitrate is 10 mg/L.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station (Susan River above confluence with Willard Creek) was sampled.
Temporal Representation: | Sixteen quarterly samples (3 to 4 per year) were collected between 2001 and 2005.
Environmental Conditions: | The Susan River is an internally drained river in eastern Lassen County with its headwaters near Lassen Volcanic National Park and its terminus in Honey Lake in the Great Basin. The Susan River is designated for both the Warm Freshwater Habitat and Cold Freshwater Habitat beneficial uses, and for the Spawning, Reproduction and Development and Migration of Aquatic Organisms uses.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 21343 | Region 6
Susan River (Headwaters to Susanville)

Pollutant: | Oxygen, Dissolved
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)(2010)
Revision Status | Original
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. Three of the SWAMP samples exceed the water quality objective. None of the USBLM samples exceeds the objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The SWAMP data used satisfy the data quality requirements of section 6.1.4 of the Policy. No quality assurance information was submitted with the USBLM data. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of. the Policy. The quarterly SWAMP samples do not capture the seasonal and annual variability expected in streamflows and constituent concentrations in streams of the Lahontan Region. 3. Three of twelve SWAMP samples exceeded the water quality objective. Neither of two USBLM samples exceeded the objective and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | No new data were assessed for this assessment cycle. The conclusion reached in the previous cycle remains in same. The Regional Board will update this decision when new data and information become available in a future assessment cycle.

Line of Evidence (LOE) for Decision ID 21343, Oxygen, Dissolved | Region 6
Susan River (Headwaters to Susanville)
LOE ID: | 26010
Pollutant: | Oxygen, Dissolved
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Bureau of Land Management sampled the Susan River in June, July and August 2002. Dissolved oxygen concentrations in two samples were 9.36 and 8.9 mg/L.
Data Reference: | Water quality data for surface waters on U.S Bureau of Land Management lands in Lassen and Modoc Counties
SWAMP Data: | Non-SWAMP
Water Quality Objective/Criterion: | The applicable water quality objective, from Lahontan Basin Plan Table 3-6, is a 1day minimum dissolved oxygen concentration of 8 mg/L.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | The USBLM sampled three stations, Susan River at Hobo Camp and Susan River at Devils Corral, and Susan River above Cheney Creek..
Temporal Representation: | Samples were collected on June 5, July 16 and August 19, 2002.
Environmental Conditions: | The Susan River is an internally drained river in eastern Lassen County with its headwaters near Lassen Volcanic National Park and its terminus in Honey Lake in the Great Basin. The Susan River is designated for both the Warm Freshwater Habitat and Cold Freshwater Habitat beneficial uses, and for the Spawning, Reproduction and Development and Migration of Aquatic Organisms uses.
QAPP Information: | No quality assurance information was submitted with the USBLM data.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 21343, Oxygen, Dissolved | Region 6
Susan River (Headwaters to Susanville)
LOE ID: | 6917
Pollutant: | Oxygen, Dissolved
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 12
Number of Exceedances: | 3
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled the Susan River under the Region 6 SWAMP program between 2002 and 2005. Concentrations of dissolved oxygen in 12 quarterly samples ranged from 7.2 to 12.3 mg/L. Three samples were below the 8 mg/L minimum concentration.
Data Reference: | 2007. SWAMP Data for the Susan River
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | The water quality objective, from Lahontan Basin Plan Table 3-6, is a one day minimum dissolved oxygen concentration of 8 mg/L.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station (Susan River above confluence with Willard Creek) was sampled.
Temporal Representation: | Twelve quarterly samples (3 to 4 per year) were taken between 2002 and 2005.
Environmental Conditions: | The Susan River is an internally drained river in eastern Lassen County with its headwaters near Lassen Volcanic National Park and its terminus in Honey Lake in the Great Basin. The Susan River is designated for both the Warm Freshwater Habitat and Cold Freshwater Habitat beneficial uses, and for the Spawning, Reproduction and Development and Migration of Aquatic Organisms uses.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30093 | Region 6
Susan River (Headwaters to Susanville)

Pollutant: | Phosphate
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)(2010)
Revision Status | Original
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Two lines of evidence, from two different datasets, are available in the administrative record to assess this pollutant. No biological data are available for assessment of compliance with the water quality objective for biostimulatory substances. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. One of the datasets used satisfies the data quality requirements of section 6.1.4 of the Policy. The other does not. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. One dataset consists of a single sample and the other of five samples collected in two summer months. 3. No biological data are available for assessment of compliance with the water quality objective and the data cannot be assessed using Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | No new data were assessed for this assessment cycle. The conclusion reached in the previous cycle remains in same. The Regional Board will update this decision when new data and information become available in a future assessment cycle.

Line of Evidence (LOE) for Decision ID 30093, Phosphate | Region 6
Susan River (Headwaters to Susanville)
LOE ID: | 23455
Pollutant: | Phosphate
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled the Susan River under the Region 6 SWAMP program. A single sample for dissolved phosphate was collected on March 23, 2004. The concentration was 0.011 mg/L.
Data Reference: | 2007. SWAMP Data for the Susan River
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | The Lahontan Basin Plan does not include a site-specific objective (SSO) for phosphate in the Susan River. The narrative objective for biostimulatory substances states: "Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect the water for beneficial uses."
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station (Susan River above confluence with Willard Creek) was sampled.
Temporal Representation: | One sample was collected on March 23, 2004.
Environmental Conditions: | The Susan River is an internally drained river in eastern Lassen County with its headwaters near Lassen Volcanic National Park and its terminus in Honey Lake in the Great Basin. The Susan River is designated for both the Warm Freshwater Habitat and Cold Freshwater Habitat beneficial uses, and for the Spawning, Reproduction and Development and Migration of Aquatic Organisms uses.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30093, Phosphate | Region 6
Susan River (Headwaters to Susanville)
LOE ID: | 26254
Pollutant: | Phosphate
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 5
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Bureau of Land Management sampled the Susan River in June, July and August 2002. Concentrations of PO4-P in 5 samples ranged from 0.22 to 0.75 mg/L.
Data Reference: | Water quality data for surface waters on U.S Bureau of Land Management lands in Lassen and Modoc Counties
SWAMP Data: | Non-SWAMP
Water Quality Objective/Criterion: | The Lahontan Basin Plan does not include a site-specific objective (SSO) for phosphate in the Susan River. The narrative objective for biostimulatory substances states: "Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect the water for beneficial uses."
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | The USBLM sampled three stations, Susan River at Hobo Camp, Susan River at Devils Corral, and Susan River above Cheney Creek.
Temporal Representation: | Samples were collected on June 5, July 16, and August 19, 2002.
Environmental Conditions: | The Susan River is an internally drained river in eastern Lassen County with its headwaters near Lassen Volcanic National Park and its terminus in Honey Lake in the Great Basin. The Susan River is designated for both the Warm Freshwater Habitat and Cold Freshwater Habitat beneficial uses, and for the Spawning, Reproduction and Development and Migration of Aquatic Organisms uses.
QAPP Information: | No quality assurance information was submitted with the data.
QAPP Information Reference(s):

DECISION ID | 28543 | Region 6
Susan River (Headwaters to Susanville)

Pollutant: | Phosphorus
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)(2010)
Revision Status | Original
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. One annual average datapoint exceeds the site-specific water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used do not satisfy the data quality requirements of section 6.1.4 of the Policy due to an error in the SWAMP QAPP regarding holding times for total phosphorus samples. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. Quarterly samples do not capture the full range of seasonal and annual variability in streamflows and constituent concentrations expected in streams of the Lahontan Region. 3. One of five annual average datapoints exceeded the site-specific water quality objective and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | No new data were assessed for this assessment cycle. The conclusion reached in the previous cycle remains in same. The Regional Board will update this decision when new data and information become available in a future assessment cycle.

Line of Evidence (LOE) for Decision ID 28543, Phosphorus | Region 6
Susan River (Headwaters to Susanville)
LOE ID: | 23456
Pollutant: | Phosphorus
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 5
Number of Exceedances: | 1
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled the Susan River under the Region 6 SWAMP program between 2001 and1005. Concentrations of total phosphorus in 16 quarterly samples included three estimated values. Concentrations in the remainder of the samples ranged from 0.028 to 0.087 mg/L. Because of the estimated values in individual samples, the annual averages for 2001 and 2002 are estimates. Annual averages in the remaining 3 years (based on 3 to 4 samples per year) are j0.050, 0.054 and 0.066 mg/L. One of these averages exceeds the objective.
Data Reference: | 2007. SWAMP Data for the Susan River
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | The applicable site-specific objective, from Lahontan Basin Plan Table 3-9, is an annual average total phosphorus concentration of 0.06 mg/L.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station (Susan River above confluence with Willard Creek) was sampled.
Temporal Representation: | Sixteen quarterly samples (3 to 4 per year) were taken between 2001 and 2005.
Environmental Conditions: | The Susan River is an internally drained river in eastern Lassen County with its headwaters near Lassen Volcanic National Park and its terminus in Honey Lake in the Great Basin. The Susan River is designated for both the Warm Freshwater Habitat and Cold Freshwater Habitat beneficial uses, and for the Spawning, Reproduction and Development and Migration of Aquatic Organisms uses.
QAPP Information: | Sampling and analysis were done according to the SWAMP QAPP. However, in July 2009 an error was discovered in the QAPP related to holding times for total phosphorus samples that affects the validity of data for the Lahontan Region The holding time for samples that are not acid-preserved.should be 48 hours rather than 28 days as indicated in the QAPP. "Low level" phosphorus analyses, without acid preservation, are used in the Lahontan Region's SWAMP program. .
QAPP Information Reference(s):

DECISION ID | 27351 | Region 6
Susan River (Headwaters to Susanville)

Pollutant: | Sediment
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)(2010)
Revision Status | Original
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: The Lahontan Basin Plan's narrative water quality objective is an antidegradation based objective that provides that there shall be no increases in suspended sediment concentrations or loads. This pollutant is being considered for placement on the section 303(d) list under section 3.10 of the Listing Policy, which deals with trends in water quality. Two lines of evidence are available in the administrative record to assess this pollutant. The SWAMP dataset includes quarterly 16 suspended sediment concentration values and 16 suspended sediment load values calculated from instantaneous discharge measurements. The USBLM dataset consists of five samples collected over a three-month period. Suspended sediment concentrations and loads are dependent on flows and can change rapidly over a short time during storm or snowmelt runoff events. Quarterly samples are insufficient to capture these short term events and therefore are insufficient to define natural background suspended sediment concentrations and loads, or to detect trends. Listing Policy Section 3.10 requires that natural background conditions be established. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The SWAMP data used satisfy the data quality requirements of section 6.1.4 of the Policy. No quality assurance information was submitted with the USBLM data. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. The quarterly SWAMP samples do not capture the seasonal and annual variability expected in streamflows and constituent concentrations in streams of the Lahontan Region. 3. Sampling frequency was insufficient to establish natural background conditions and therefore does not meet the requirements of Listing Policy Section 3.10.. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | No new data were assessed for this assessment cycle. The conclusion reached in the previous cycle remains in same. The Regional Board will update this decision when new data and information become available in a future assessment cycle.

Line of Evidence (LOE) for Decision ID 27351, Sediment | Region 6
Susan River (Headwaters to Susanville)
LOE ID: | 26009
Pollutant: | Sediment
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 5
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Bureau of Land Management sampled the Susan River in June, July and August 2002. Suspended sediment concentrations in 5 samples ranged from 5.4 to 24.3 mg/L.
Data Reference: | Water quality data for surface waters on U.S Bureau of Land Management lands in Lassen and Modoc Counties
SWAMP Data: | Non-SWAMP
Water Quality Objective/Criterion: | The objective from the Lahontan Basin Plan states: "The suspended sediment load and suspended sediment discharge rate of surface waters shall not be altered in such a manner as to cause nuisance or adversely affect the water for beneficial uses."
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | The USBLM sampled three stations, Susan River at Hobo Camp, Susan River at Devils Corral, and Susan River above Cheney Creek.
Temporal Representation: | Samples were collected on June 5, July 16, and August 19, 2002.
Environmental Conditions: | The Susan River is an internally drained river in eastern Lassen County with its headwaters near Lassen Volcanic National Park and its terminus in Honey Lake in the Great Basin. The Susan River is designated for both the Warm Freshwater Habitat and Cold Freshwater Habitat beneficial uses, and for the Spawning, Reproduction and Development and Migration of Aquatic Organisms uses.
QAPP Information: | No quality assurance information was submitted with the USBLM data.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 27351, Sediment | Region 6
Susan River (Headwaters to Susanville)
LOE ID: | 23460
Pollutant: | Sediment
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 12
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled the Susan River under the Region 6 SWAMP program between 2002 and 2005. One of twelve suspended sediment samples was below the detection level. Concentrations in the rest of the samples ranged from 2 to 46 mg/L. Instantaneous discharge flows for the suspended sediment sampling dates ranged from 5.8 to 103 cubic feet per second. Eight suspended sediment load calculations were done; one of these was below detection level. The remainder ranged from 0.14 to 9.8 tons per day.
Data Reference: | 2007. SWAMP Data for the Susan River
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | The objective from the Lahontan Basin Plan states: "The suspended sediment load and suspended sediment discharge rate of surface waters shall not be altered in such a manner as to cause nuisance or adversely affect the water for beneficial uses."
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station (Susan River above confluence with Willard Creek) was sampled.
Temporal Representation: | Twelve quarterly samples (2 to 4 per year) were taken between 2002 and 2005.
Environmental Conditions: | The Susan River is an internally drained river in eastern Lassen County with its headwaters near Lassen Volcanic National Park and its terminus in Honey Lake in the Great Basin. The Susan River is designated for both the Warm Freshwater Habitat and Cold Freshwater Habitat beneficial uses, and for the Spawning, Reproduction and Development and Migration of Aquatic Organisms uses.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 21379 | Region 6
Susan River (Headwaters to Susanville)

Pollutant: | Specific Conductance
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)(2010)
Revision Status | Original
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. None of the samples exceeds the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The SWAMP data used satisfy the data quality requirements of section 6.1.4 of the Policy. No quality assurance information was submitted with the USBLM data. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. The quarterly SWAMP samples do not capture the seasonal and annual variability expected in streamflows and dissolved ion concentrations in streams of the Lahontan Region. 3. None of 16 SWAMP samples or 5 USBLM samples exceeded the water quality objective and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | No new data were assessed for this assessment cycle. The conclusion reached in the previous cycle remains in same. The Regional Board will update this decision when new data and information become available in a future assessment cycle.

Line of Evidence (LOE) for Decision ID 21379, Specific Conductance | Region 6
Susan River (Headwaters to Susanville)
LOE ID: | 6919
Pollutant: | Specific Conductance
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Municipal & Domestic Supply
Number of Samples: | 16
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled the Susan River under the Region 6 SWAMP program between 2001 and 2005. Specific conductance in 16 quarterly field measurements ranged from 56 to 166 uS/cm. Specific conductance in one additional laboratory measurement was 158 uS/cm. The MCL was not exceeded.
Data Reference: | 2007. SWAMP Data for the Susan River
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | California Maximum Contaminant Levels (MCLs) apply to ambient waters under the Lahontan Basin Plan's "Chemical Constituents" objective. The MCL for specific conductance is 900 microsiemens per centimeter (uS/cm).
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station (Susan River above confluence with Willard Creek) was sampled.
Temporal Representation: | Sixteen quarterly field measurements of specific conductance (3 to 4 per year) were taken between 2001 and 2005. One laboratory measurement was taken on September 9, 2003.
Environmental Conditions: | The Susan River is an internally drained river in eastern Lassen County with its headwaters near Lassen Volcanic National Park and its terminus in Honey Lake in the Great Basin. The Susan River is designated for both the Warm Freshwater Habitat and Cold Freshwater Habitat beneficial uses, and for the Spawning, Reproduction and Development and Migration of Aquatic Organisms uses.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 21379, Specific Conductance | Region 6
Susan River (Headwaters to Susanville)
LOE ID: | 26000
Pollutant: | Specific Conductance
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Municipal & Domestic Supply
Number of Samples: | 5
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Bureau of Land Management sampled the Susan River in June, July and August 2002. Specific conductance in 5 samples ranged from 109 to 169 uS/cm. The MCL was not violated.
Data Reference: | Water quality data for surface waters on U.S Bureau of Land Management lands in Lassen and Modoc Counties
SWAMP Data: | Non-SWAMP
Water Quality Objective/Criterion: | California Maximum Contaminant Levels (MCLs) apply to ambient waters under the Lahontan Basin Plan's "Chemical Constituents" objective. The MCL for specific conductance is 900 microsiemens per centimeter (uS/cm).
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
| Water quality data for surface waters on U.S Bureau of Land Management lands in Lassen and Modoc Counties
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | The USBLM sampled three stations, Susan River at Hobo Camp, Susan River at Devils Corral, and susan River above Cheney Creek.
Temporal Representation: | Samples were collected on June 5, July 16, and August 19, 2002.
Environmental Conditions: | The Susan River is an internally drained river in eastern Lassen County with its headwaters near Lassen Volcanic National Park and its terminus in Honey Lake in the Great Basin. The Susan River is designated for both the Warm Freshwater Habitat and Cold Freshwater Habitat beneficial uses, and for the Spawning, Reproduction and Development and Migration of Aquatic Organisms uses.
QAPP Information: | No quality assurance information was submitted with the USBLM data.
QAPP Information Reference(s):

DECISION ID | 27350 | Region 6
Susan River (Headwaters to Susanville)

Pollutant: | Temperature, water
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)(2010)
Revision Status | Original
Impairment from Pollutant or Pollution: | Pollution
Regional Board Staff Conclusion: | Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: The Lahontan Basin Plan's narrative temperature objective is an antidegradation-based objective that requires that there be no change in temperature in waters designated for the Cold Freshwater Habitat (COLD) beneficial use. The objective does not include specific numerical limits for protection of the COLD use. Listing Policy Section 3.10 contains directions for assessment based on trends in water quality. These directions include requirements to establish specific baseline conditions and specify the influence of seasonal and interannual effects. One line of evidence is available to support this decision. There are not enough temperature samples to establish baseline conditions (including diel, seasonal, annual and interannual variations in temperature) or to detect declining trends in the temperature regime if such trends exist. Because temperature samples were collected only quarterly, weekly and monthly average data are not available for comparison with guidelines in the scientific literature for the temperature requirements of sensitive aquatic species such as salmonids, as directed in Listing Policy Section 6.1.5.9.
Regional Board Staff Decision Recommendation: | No new data were assessed for this assessment cycle. The conclusion reached in the previous cycle remains in same. The Regional Board will update this decision when new data and information become available in a future assessment cycle.

Line of Evidence (LOE) for Decision ID 27350, Temperature, water | Region 6
Susan River (Headwaters to Susanville)
LOE ID: | 6916
Pollutant: | Temperature, water
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 16
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled the Susan River under the Region 6 SWAMP program between 2001 and 2005. Temperatures in 16 quarterly field measurements ranged from 2 to 21 degrees Celsius.
Data Reference: | 2007. SWAMP Data for the Susan River
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | The applicable language from the Lahontan Basin Plan's water quality objective for temperature states: "The natural receiving water temperature of all waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such an alteration in temperature does not adversely affect the water for beneficial uses. For waters designated WARM, water temperature shall not be altered by more than five degrees Fahrenheit ... above or below the natural temperature. For waters designated COLD, the temperature shall not be altered."
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station (Susan River above confluence with Willard Creek) was sampled.
Temporal Representation: | Sixteen quarterly temperature measurements (3 to 4 per year) were taken between 2001 and 2005.
Environmental Conditions: | The Susan River is an internally drained river in eastern Lassen County with its headwaters near Lassen Volcanic National Park and its terminus in Honey Lake in the Great Basin. The Susan River is designated for both the Warm Freshwater Habitat and Cold Freshwater Habitat beneficial uses, and for the Spawning, Reproduction and Development and Migration of Aquatic Organisms uses.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 27350, Temperature, water | Region 6
Susan River (Headwaters to Susanville)
LOE ID: | 26003
Pollutant: | Temperature, water
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 5
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Bureau of Land Management sampled the Susan River in June, July and August 2002. Water temperatures in 5 samples ranged from 13.2 to 22 degrees Celsius.
Data Reference: | Water quality data for surface waters on U.S Bureau of Land Management lands in Lassen and Modoc Counties
SWAMP Data: | Non-SWAMP
Water Quality Objective/Criterion: | The applicable language from the Lahontan Basin Plan's water quality objective for temperature states: "The natural receiving water temperature of all waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such an alteration in temperature does not adversely affect the water for beneficial uses. For waters designated WARM, water temperature shall not be altered by more than five degrees Fahrenheit ... above or below the natural temperature. For waters designated COLD, the temperature shall not be altered."
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | The USBLM sampled three stations, Susan River at Hobo Camp, Susan River at Devils Corral, and Susan River above Cheney Creek.
Temporal Representation: | Samples were collected on June 5, July 16, and August 19, 2002.
Environmental Conditions: | The Susan River is an internally drained river in eastern Lassen County with its headwaters near Lassen Volcanic National Park and its terminus in Honey Lake in the Great Basin. The Susan River is designated for both the Warm Freshwater Habitat and Cold Freshwater Habitat beneficial uses, and for the Spawning, Reproduction and Development and Migration of Aquatic Organisms uses.
QAPP Information: | No quality assurance information was submitted with the USBLM data.
QAPP Information Reference(s):

DECISION ID | 27348 | Region 6
Susan River (Headwaters to Susanville)

Pollutant: | Total Kjeldahl Nitrogen (TKN)
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)(2010)
Revision Status | Original
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. No biological data are available for assessment of compliance with the water quality objective for biostimulatory substances. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. Quarterly samples do not capture the seasonal and annual variability expected in streamflows and constituent concentrations in streams of the Lahontan Region. 3. No biological data are available to assess compliance with the water quality objective. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | No new data were assessed for this assessment cycle. The conclusion reached in the previous cycle remains in same. The Regional Board will update this decision when new data and information become available in a future assessment cycle.

Line of Evidence (LOE) for Decision ID 27348, Total Kjeldahl Nitrogen (TKN) | Region 6
Susan River (Headwaters to Susanville)
LOE ID: | 23452
Pollutant: | Total Kjeldahl Nitrogen (TKN)
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 16
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled the Susan River under the Region 6 SWAMP program between 2001 and1005. Concentrations of TKN in 16 quarterly samples ranged from 0.1 to 0.64 mg/L.
Data Reference: | 2007. SWAMP Data for the Susan River
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | The Lahontan Basin Plan does not include a site-specific objective (SSO) for total Kjeldahl nitrogen (TKN) in the Susan River. The narrative objective for biostimulatory substances states: "Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect the water for beneficial uses."
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station (Susan River above confluence with Willard Creek) was sampled.
Temporal Representation: | Sixteen quarterly samples (3 to 4 per year) were taken between 2001 and 2005.
Environmental Conditions: | The Susan River is an internally drained river in eastern Lassen County with its headwaters near Lassen Volcanic National Park and its terminus in Honey Lake in the Great Basin. The Susan River is designated for both the Warm Freshwater Habitat and Cold Freshwater Habitat beneficial uses, and for the Spawning, Reproduction and Development and Migration of Aquatic Organisms uses.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 27383 | Region 6
Susan River (Headwaters to Susanville)

Pollutant: | Turbidity
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)(2010)
Revision Status | Original
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Six lines of evidence are available in the administrative record to assess this pollutant. Separate lines of evidence were prepared for data expressed as NTU and NTRU. The two types of units are measured differently and are not directly comparable. There are no specific state or federal standards or criteria for turbidity expressed as NTRU. One of the SWAMP samples expressed as NTU, and three of the USBLM samples, exceed the Maximum Contaminant level. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The SWAMP data used satisfy the data quality requirements of section 6.1.4 of the Policy. No quality assurance information was submitted with the USBLM data. 2. The data used satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. One of 12 SWAMP samples and 3 of 5 USBLM samples expressed as NTU exceeded the Maximum Contaminant Level and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | No new data were assessed for this assessment cycle. The conclusion reached in the previous cycle remains the same. The Regional Board will update this decision when new data and information become available in a future assessment cycle.

Line of Evidence (LOE) for Decision ID 27383, Turbidity | Region 6
Susan River (Headwaters to Susanville)
LOE ID: | 26008
Pollutant: | Turbidity
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Municipal & Domestic Supply
Number of Samples: | 5
Number of Exceedances: | 3
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Bureau of Land Management sampled the Susan River in June, July and August 2002. Turbidity in five samples ranged from 0.8 to 10.6 NTU. Three of five samples exceeded the MCL.
Data Reference: | Water quality data for surface waters on U.S Bureau of Land Management lands in Lassen and Modoc Counties
SWAMP Data: | Non-SWAMP
Water Quality Objective/Criterion: | California Maximum Contaminant Levels (MCLs) apply to ambient waters under the Lahontan Basin Plan's "Chemical Constituents" objective. The MCL for turbidity is 5 NTU.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | The USBLM sampled three stations, Susan River at Hobo Camp, Susan River at Devils Corral, and Susan River above Cheney Creek.
Temporal Representation: | Samples were collected on June 5, July 16, and August 19, 2002.
Environmental Conditions: | The Susan River is an internally drained river in eastern Lassen County with its headwaters near Lassen Volcanic National Park and its terminus in Honey Lake in the Great Basin. The Susan River is designated for both the Warm Freshwater Habitat and Cold Freshwater Habitat beneficial uses, and for the Spawning, Reproduction and Development and Migration of Aquatic Organisms uses.
QAPP Information: | No quality assurance information was submitted with the USBLM data.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 27383, Turbidity | Region 6
Susan River (Headwaters to Susanville)
LOE ID: | 26005
Pollutant: | Turbidity
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 5
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Bureau of Land Management sampled the Susan River in June, July and August 2002. Turbidity in 5 samples ranged from 0.8 to 10.6 NTU.
Data Reference: | Water quality data for surface waters on U.S Bureau of Land Management lands in Lassen and Modoc Counties
SWAMP Data: | Non-SWAMP
Water Quality Objective/Criterion: | The Lahontan Basin Plan's regionwide turbidity objective states: "Waters shall be free of changes in turbidity that cause nuisance or adversely affect the water for beneficial uses. Increases in turbidity shall not exceed natural levels by more than 10 percent."
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | The USBLM sampled three stations, Susan River at Hobo Camp, Susan River at Devils Corral, and Susan River above Cheney Creek.
Temporal Representation: | Samples were collected on June 5, July 16, and August 19, 2002.
Environmental Conditions: | The Susan River is an internally drained river in eastern Lassen County with its headwaters near Lassen Volcanic National Park and its terminus in Honey Lake in the Great Basin. The Susan River is designated for both the Warm Freshwater Habitat and Cold Freshwater Habitat beneficial uses, and for the Spawning, Reproduction and Development and Migration of Aquatic Organisms uses.
QAPP Information: | No quality assurance information was submitted with the USBLM data.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 27383, Turbidity | Region 6
Susan River (Headwaters to Susanville)
LOE ID: | 23461
Pollutant: | Turbidity
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 12
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled the Susan River under the Region 6 SWAMP program between 2001 and 2004. One of 12 quarterly measurements of turbidity as NTU was below the detection level; the remainder ranged from 0.7 to 12 NTU.
Data Reference: | 2007. SWAMP Data for the Susan River
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | The Lahontan Basin Plan's regionwide turbidity objective states: "Waters shall be free of changes in turbidity that cause nuisance or adversely affect the water for beneficial uses. Increases in turbidity shall not exceed natural levels by more than 10 percent."
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station (Susan River above confluence with Willard Creek) was sampled.
Temporal Representation: | Twelve quarterly turbidity measurements expressed as NTU (3 to 4 per year) were taken between 2001 and 2004.
Environmental Conditions: | The Susan River is an internally drained river in eastern Lassen County with its headwaters near Lassen Volcanic National Park and its terminus in Honey Lake in the Great Basin. The Susan River is designated for both the Warm Freshwater Habitat and Cold Freshwater Habitat beneficial uses, and for the Spawning, Reproduction and Development and Migration of Aquatic Organisms uses.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 27383, Turbidity | Region 6
Susan River (Headwaters to Susanville)
LOE ID: | 23469
Pollutant: | Turbidity
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Municipal & Domestic Supply
Number of Samples: | 4
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled the Susan River under the Region 6 SWAMP program between 2004 and 2005. Two of four quarterly samples were below the detection level. Turbidity values in the other samples were 2.5 and 37 NTRU.
Data Reference: | 2007. SWAMP Data for the Susan River
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for turbidity expressed as NTRU for the protection of human health.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station (Susan River above confluence with Willard Creek) was sampled.
Temporal Representation: | Four quarterly turbidity measurements expressed as NTRU were taken in 2004 and 2005.
Environmental Conditions: | The Susan River is an internally drained river in eastern Lassen County with its headwaters near Lassen Volcanic National Park and its terminus in Honey Lake in the Great Basin. The Susan River is designated for both the Warm Freshwater Habitat and Cold Freshwater Habitat beneficial uses, and for the Spawning, Reproduction and Development and Migration of Aquatic Organisms uses.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 27383, Turbidity | Region 6
Susan River (Headwaters to Susanville)
LOE ID: | 23462
Pollutant: | Turbidity
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Municipal & Domestic Supply
Number of Samples: | 12
Number of Exceedances: | 1
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled the Susan River under the Region 6 SWAMP program between 2001 and 2004. One of 12 quarterly measurements of turbidity as NTU was below the detection level; the remainder ranged from 0.7 to 12 NTU. One sample exceeded the MCL.
Data Reference: | 2007. SWAMP Data for the Susan River
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | California Maximum Contaminant Levels (MCLs) apply to ambient waters under the Lahontan Basin Plan's "Chemical Constituents" objective. The MCL for turbidity is 5 NTU.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station (Susan River above confluence with Willard Creek) was sampled.
Temporal Representation: | Twelve quarterly turbidity measurements expressed as NTU (3 to 4 per year) were taken between 2001 and 2004.
Environmental Conditions: | The Susan River is an internally drained river in eastern Lassen County with its headwaters near Lassen Volcanic National Park and its terminus in Honey Lake in the Great Basin. The Susan River is designated for both the Warm Freshwater Habitat and Cold Freshwater Habitat beneficial uses, and for the Spawning, Reproduction and Development and Migration of Aquatic Organisms uses.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 27383, Turbidity | Region 6
Susan River (Headwaters to Susanville)
LOE ID: | 23468
Pollutant: | Turbidity
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 4
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled the Susan River under the Region 6 SWAMP program between 2004 and 2005. Two of four quarterly samples were below the detection level. Turbidity values in the other samples were 2.5 and 37 NTRU.
Data Reference: | 2007. SWAMP Data for the Susan River
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | The Lahontan Basin Plan's regionwide turbidity objective states: "Waters shall be free of changes in turbidity that cause nuisance or adversely affect the water for beneficial uses. Increases in turbidity shall not exceed natural levels by more than 10 percent."
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station (Susan River above confluence with Willard Creek) was sampled.
Temporal Representation: | Four quarterly turbidity measurements expressed as NTRU were taken in 2004 and 2005.
Environmental Conditions: | The Susan River is an internally drained river in eastern Lassen County with its headwaters near Lassen Volcanic National Park and its terminus in Honey Lake in the Great Basin. The Susan River is designated for both the Warm Freshwater Habitat and Cold Freshwater Habitat beneficial uses, and for the Spawning, Reproduction and Development and Migration of Aquatic Organisms uses.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 27382 | Region 6
Susan River (Headwaters to Susanville)

Pollutant: | pH
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)(2010)
Revision Status | Original
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: The Lahontan Basin Plan's narrative pH objective is an antidegradation-based objective that requires that there be no change greater than 0.5 pH units in waters designated for the Cold Freshwater Habitat (COLD) or Warm Freshwater Habitat beneficial uses. A pH range of 6.5 to 8.5 units applies to "all other waters". Listing Policy Section 3.10 contains directions for assessment based on trends in water quality. These directions include requirements to establish specific baseline conditions and specify the influence of seasonal and interannual effects. Two lines of evidence are available to support this decision. No quality assurance information was submitted with the USBLM data. There are not enough pH samples to establish baseline conditions (including diel, seasonal, annual and interannual variations) or to detect changes in the pH regime due to controllable factors, if such trends exist.
Regional Board Staff Decision Recommendation: | No new data were assessed for this assessment cycle. The conclusion reached in the previous cycle remains in same. The Regional Board will update this decision when new data and information become available in a future assessment cycle.

Line of Evidence (LOE) for Decision ID 27382, pH | Region 6
Susan River (Headwaters to Susanville)
LOE ID: | 26002
Pollutant: | pH
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 5
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Bureau of Land Management sampled the Susan River in June, July and August 2002. Five sampes had pH ranging from 7.6 to 8.9 units.
Data Reference: | Water quality data for surface waters on U.S Bureau of Land Management lands in Lassen and Modoc Counties
SWAMP Data: | Non-SWAMP
Water Quality Objective/Criterion: | The objective in the Lahontan Basin Plan states: "In fresh waters with designated beneficial uses of COLD or WARM, changes in normal ambient pH levels shall not exceed 0.5 pH units. For all other waters of the region, the pH shall not be depressed below 6.5 nor raised above 8.5 units. The Regional Board recognizes that some waters of the Region may have natural pH levels outside of the 6.5 to 8.5 range. Compliance with the pH objective for these waters will be determined on a case-by-case basis."
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | The USBLM sampled three stations, Susan River at Hobo Camp, Susan River at Devils Corral, and susan River above Cheney Creek.
Temporal Representation: | Samples were collected on June 5, July 16, and August 19, 2002.
Environmental Conditions: | The Susan River is an internally drained river in eastern Lassen County with its headwaters near Lassen Volcanic National Park and its terminus in Honey Lake in the Great Basin. The Susan River is designated for both the Warm Freshwater Habitat and Cold Freshwater Habitat beneficial uses, and for the Spawning, Reproduction and Development and Migration of Aquatic Organisms uses.
QAPP Information: | No quality assurance information was submitted with the USBLM data.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 27382, pH | Region 6
Susan River (Headwaters to Susanville)
LOE ID: | 6920
Pollutant: | pH
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 15
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled the Susan River under the Region 6 SWAMP program between 2001 and 2005. The range of pH in 15 quarterly field measurements was 7.5 to 8.8 units. One measurement was above 8.5. An additional laboratory measurement was 8.1 units.
Data Reference: | 2007. SWAMP Data for the Susan River
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | The objective in the Lahontan Basin Plan states: "In fresh waters with designated beneficial uses of COLD or WARM, changes in normal ambient pH levels shall not exceed 0.5 pH units. For all other waters of the region, the pH shall not be depressed below 6.5 nor raised above 8.5 units. The Regional Board recognizes that some waters of the Region may have natural pH levels outside of the 6.5 to 8.5 range. Compliance with the pH objective for these waters will be determined on a case-by-case basis."
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station (Susan River above confluence with Willard Creek) was sampled.
Temporal Representation: | Fifteen quarterly field measurements of pH (3 to 4 per year) were taken between 2001 and 2005. One laboratory measurement was taken on September 9, 2003.
Environmental Conditions: | The Susan River is an internally drained river in eastern Lassen County with its headwaters near Lassen Volcanic National Park and its terminus in Honey Lake in the Great Basin. The Susan River is designated for both the Warm Freshwater Habitat and Cold Freshwater Habitat beneficial uses, and for the Spawning, Reproduction and Development and Migration of Aquatic Organisms uses.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 29656 | Region 6
Susan River (Headwaters to Susanville)

Pollutant: | Total Dissolved Solids
Final Listing Decision: | List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | List on 303(d) list (TMDL required list)(2010)
Revision Status | Original
Sources: | Source Unknown
Expected TMDL Completion Date: | 2021
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: State Board Review and Conclusion: The April 19, 2010 State Water Board staff report for the 2010 Integrated Report recommended to place this water body on the 303(d) list for total nitrogen based on the State Water Board staff determination that the data were collected over a broad period of time to meet section 6.1.5.3 of the Listing Policy. The State Water Board recommendation is based on the following: Lahontan Regional Board staff had decided not to list this water body because staff thought it had insufficient information to make a decision to list. However, State Board staff finds there are 5 samples to make a decision and this meets the sample size requirements of Table 3.1 of the Listing Policy. State Water Board staff re-evaluated the available data and the recommendation has been revised. On August 4, 2010 the State Water Board approved the staff recommendation to place this water body-pollutant combination on the 303(d) list. The final language for the recommendation is: Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. The single sample in one dataset exceeds the objective and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. Three of five annual average datapoints in the other dataset samples exceeded the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.State Board Review and Conclusion:
Regional Board Staff Decision Recommendation: | No new data were assessed for this assessment cycle. The conclusion reached in the previous cycle remains the same. The Regional Board will update this decision when new data and information become available in a future assessment cycle.

Line of Evidence (LOE) for Decision ID 29656, Total Dissolved Solids | Region 6
Susan River (Headwaters to Susanville)
LOE ID: | 23458
Pollutant: | Total Dissolved Solids
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total Dissolved
Beneficial Use: | Municipal & Domestic Supply
Number of Samples: | 16
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled the Susan River under the Region 6 SWAMP program between 2001 and 2005. Concentrations in 16 quarterly samples (3-4 per year) ranged from 46 to 132 mg/L. The MCL was not exceeded.
Data Reference: | 2007. SWAMP Data for the Susan River
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | California Maximum Contaminant Levels (MCLs) apply to ambient waters under the Lahontan Basin Plan's "Chemical Constituents" objective. The recommended MCL for total dissolved solids (TDS) is 500 mg/L.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station (Susan River above confluence with Willard Creek) was sampled.
Temporal Representation: | Sixteen quarterly samples (3 to 4 per year) were collected between 2001 and 2005.
Environmental Conditions: | The Susan River is an internally drained river in eastern Lassen County with its headwaters near Lassen Volcanic National Park and its terminus in Honey Lake in the Great Basin. The Susan River is designated for both the Warm Freshwater Habitat and Cold Freshwater Habitat beneficial uses, and for the Spawning, Reproduction and Development and Migration of Aquatic Organisms uses.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 29656, Total Dissolved Solids | Region 6
Susan River (Headwaters to Susanville)
LOE ID: | 23457
Pollutant: | Total Dissolved Solids
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total Dissolved
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 5
Number of Exceedances: | 5
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled the Susan River under the Region 6 SWAMP program between 2001 and 2005. Concentrations in 16 quarterly samples (3-4 per year) ranged from 46 to 132 mg/L. Annual averages ranged from 77 to 125 mg/L. The site-specific objective was exceeded in 5 of 5 years.
Data Reference: | 2007. SWAMP Data for the Susan River
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | The site-specific objective from Lahontan Basin Plan Table 3-9 includes an annual average Total Dissolved Solids (TDS) concentration of 60 mg/L and a 90th percentile value of 75 mg/L.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station (Susan River above confluence with Willard Creek) was sampled.
Temporal Representation: | Sixteen quarterly samples (3 to 4 per year) were collected between 2001 and 2005.
Environmental Conditions: | The Susan River is an internally drained river in eastern Lassen County with its headwaters near Lassen Volcanic National Park and its terminus in Honey Lake in the Great Basin. The Susan River is designated for both the Warm Freshwater Habitat and Cold Freshwater Habitat beneficial uses, and for the Spawning, Reproduction and Development and Migration of Aquatic Organisms uses.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30299 | Region 6
Susan River (Headwaters to Susanville)

Pollutant: | Total Nitrogen as N
Final Listing Decision: | List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | List on 303(d) list (TMDL required list)(2010)
Revision Status | Original
Sources: | Source Unknown
Expected TMDL Completion Date: | 2021
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | Regional Board Conclusion: This pollutant was considered for placement on the section 303(d) list in a previous assessment cycle. No new information was reviewed for this current assessment cycle. Therefore, the previous conclusion remains unchanged, and is as follows: Regional Board Conclusion: This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Two lines of evidence (from different datasets) are available in the administrative record to assess this pollutant. The single sample from one dataset, and three of five annual average datapoints from the other dataset, exceed the site-specific water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. Listing is not recommended because the data are not temporally representative. This conclusion is based on the staff findings that: 1. One of the datasets used satisfies the data quality requirements of section 6.1.4 of the Policy. The other does not. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. One dataset consists of a single sample. The quarterly samples in the other dataset do not capture the full range of seasonal and annual variability in streamflows and constituent concentrations expected in streams of the Lahontan Region. 3. The single sample in one dataset exceeds the objective and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. Three of five annual average datapoints in the other dataset samples exceeded the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. State Board Review and Conclusion: The April 19, 2010 State Water Board staff report for the 2010 Integrated Report recommended to place this water body on the 303(d) list for total nitrogen based on the State Water Board staff determination that the data were collected over a broad period of time to meet section 6.1.5.3 of the Listing Policy. The State Water Board recommendation is based on the following: Lahontan Regional Board staff had decided not to list this water body because staff thought it had insufficient information to make a decision to list. However, State Board staff finds there are 5 samples to make a decision and this meets the sample size requirements of Table 3.1 of the Listing Policy. State Water Board staff re-evaluated the available data and the recommendation has been revised. On August 4, 2010 the State Water Board approved the staff recommendation to place this water body-pollutant combination on the 303(d) list. The final language for the recommendation is: Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification in favor of placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. The single sample in one dataset exceeds the objective and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. Three of five annual average datapoints in the other dataset samples exceeded the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | No new data were assessed for this assessment cycle. The conclusion reached in the previous cycle remains the same. The Regional Board will update this decision when new data and information become available in a future assessment cycle.

Line of Evidence (LOE) for Decision ID 30299, Total Nitrogen as N | Region 6
Susan River (Headwaters to Susanville)
LOE ID: | 23459
Pollutant: | Total Nitrogen as N
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 5
Number of Exceedances: | 3
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled the Susan River under the Region 6 SWAMP program between 2001 and 2005. Total nitrogen was calculated from 16 quarterly samples each for total Kjeldahl nitrogen and nitrite plus nitrate. Concentrations of total nitrogen in 16 quarterly samples included three estimated values; the remainder of the samples ranged from 0.23 and 0.66 mg/L. Two of 5 annual averages (based on 3 to 4 calcuated concentrations per year) were estimates; the remainder were 0.33, 0.30 and 0.40 mg/L. The site-specific objective was exceeded in 3 of 5 years
Data Reference: | 2007. SWAMP Data for the Susan River
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | The applicable site-specific objective, from Lahontan Basin Plan Table 3-9, includes an annual average total nitrogen concentration of 0.20 mg/L and a 90th percentile value of 0.30 mg/L.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station (Susan River above confluence with Willard Creek) was sampled.
Temporal Representation: | Sixteen quarterly samples each (3 to 4 per year) were taken for total Kjeldahl nitrogen and nitrite plus nitrate between 2001 and 2005.
Environmental Conditions: | The Susan River is an internally drained river in eastern Lassen County with its headwaters near Lassen Volcanic National Park and its terminus in Honey Lake in the Great Basin. The Susan River is designated for both the Warm Freshwater Habitat and Cold Freshwater Habitat beneficial uses, and for the Spawning, Reproduction and Development and Migration of Aquatic Organisms uses.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30299, Total Nitrogen as N | Region 6
Susan River (Headwaters to Susanville)
LOE ID: | 26253
Pollutant: | Total Nitrogen as N
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Cold Freshwater Habitat
Number of Samples: | 1
Number of Exceedances: | 1
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Bureau of Land Management sampled the Susan River in June, July and August 2002. Samples were not collected for total nitrogen. Concentrations of NO3-N in 5 samples ranged from 0.15 to 1.32 mg/L. The "annual average" calculated from these samples was 0.22 mg/L, slightly exceeding the objective.
Data Reference: | Water quality data for surface waters on U.S Bureau of Land Management lands in Lassen and Modoc Counties
SWAMP Data: | Non-SWAMP
Water Quality Objective/Criterion: | The site-specific water quality objective for total nitrogen is an annual average of 0.2 mg/L and a 90th percentile value of 0.3 mg/L.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
| Water quality data for surface waters on U.S Bureau of Land Management lands in Lassen and Modoc Counties
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | The USBLM sampled three stations, Susan River at Hobo Camp, Susan River at Devils Corral, and Susan River above Cheney Creek.
Temporal Representation: | Samples were collected on June 5, July 16, and August 19, 2002.
Environmental Conditions: | The Susan River is an internally drained river in eastern Lassen County with its headwaters near Lassen Volcanic National Park and its terminus in Honey Lake in the Great Basin. The Susan River is designated for both the Warm Freshwater Habitat and Cold Freshwater Habitat beneficial uses, and for the Spawning, Reproduction and Development and Migration of Aquatic Organisms uses.
QAPP Information: | No quality assurance information was submitted with the USBLM data.
QAPP Information Reference(s):